Chronic Myeloproliferative Disorders (CMPD)
CMPD includes CML, polycythemia vera (PCV), myelofibrosis with myeloid metaplasia (MMM), and essential thrombocythemia (ET). Each is a clonal proliferation of a pluripotent stem cell that can differentiate along granulocytic, erythroid, and megakaryocytic lines. Each has a chronic course that often terminates as acute leukemia or myelofibrosis. CMPD is more common in adults.
- PCV is characterized by excessive proliferation of all three cell lines resulting in high red cell mass, leukocytosis, and thrombocytosis.
- MMM is characterized by some degree of fibrosis of the marrow, extramedullary hematopoiesis causing massive splenomegaly, and circulating normoblasts, immature granulocytes, and abnormal platelets.
- ET is characterized by very high and persistent thrombocytosis, including presence of abnormal platelets. Bleeding problems or coagulopathy occur.
|del(13q) interstital or terminal||PCV,MMM|
|del(20)(q11.2) or (q11.2q13.1)||PCV,MMM|